There's a pretty good chance that you don't remember Oreo O's from when they were sold in this country (1998-2007), but if you were a part of the target audience at the time (young enough to eat super sugary breakfast cereals but old enough to know how awesome Oreos are), then it just might've been your favorite cereal ever.
We fall into that second category.
Apparently, a box of Oreo O's only sets you back about $5 in Korea. Unfortunately, shipping it stateside costs an extra $15 or so. Buying in bulk can save you some money, but it's still going to be some of the most expensive breakfast cereal still being produced. Is it worth it? Absolutely.